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What are the mathematical/computational principles behind this game?
... same).
Every two lines meet in exactly one point (this is a bit different from Euclid).
Now, add "finite" into the soup and you have the question:
Can we have a geometry with just 2 points? With 3 points? With 4? With 7?
There are still open questions regarding this problem but we do know this:...
What can I do with a moved-from object?
...ndard define precisely what I can do with an object once it has been moved from? I used to think that all you can do with a moved-from object is do destruct it, but that would not be sufficient.
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How does JPA orphanRemoval=true differ from the ON DELETE CASCADE DML clause
...hing. It marks "child" entity to be removed when it's no longer referenced from the "parent" entity, e.g. when you remove the child entity from the corresponding collection of the parent entity.
ON DELETE CASCADE is a database-specific thing, it deletes the "child" row in the database when the "par...
Removing an element from an Array (Java) [duplicate]
Is there any fast (and nice looking) way to remove an element from an array in Java?
15 Answers
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Extract directory from path
..."stuff/backup/file.zip" . I need a way to get the string " stuff/backup/ " from the variable $file .
5 Answers
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What is a mixin, and why are they useful?
In " Programming Python ", Mark Lutz mentions "mixins". I'm from a C/C++/C# background and I have not heard the term before. What is a mixin?
...
Throwing exceptions from constructors
I'm having a debate with a co-worker about throwing exceptions from constructors, and thought I would like some feedback.
1...
How to pass data from 2nd activity to 1st activity when pressed back? - android
...with startActivityForResult and use setResult method for sending data back from Activity2 to Activity1. In Activity1 you will need to override onActivityResult for updating TextView with EditText data from Activity2.
For example:
In Activity1, start Activity2 as:
Intent i = new Intent(this, Activ...
Post-install script with Python setuptools
...lling a source distribution zip or tarball, or installing in editable mode from a source tree. It will not work when installing from a binary wheel (.whl)
This solution is more transparent:
You will make a few additions to setup.py and there is no need for an extra file.
Also you need to consi...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...standard method, but also includes older methods and various other methods from answers to similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y=gl(3,1,6, labels=letters[1:3]),
z=c(1,2,3,3,3,2))
Using the tidyve...